Rotary engine.



0. STAFF & W. LARSON.

ROTARY ENGINE.

APPLICATION FILED JULY 6, 1909 Patented Dec. 17, 1912.

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0. STAFF & W. LARSON ROTARY ENGINE. APPLICATION FILED JULYG, 1909.

Patented Dec. 17, 1912.

4 SHEETS-SHEET 2.

0. STAFF & W. LARSON.

ROTARY ENGINE.

APPLICATION FILED JULY 6, 1909. 1,047,323 Patented Dec 17, 1912.

4 SHEETS-SHEET 3.

COLUMBIA PLANOURAPH :0" WASHINGTON, D. c.

0. STAFF & W. 'LARS'ON.

ROTARY ENGINE. APPLIGATION FILED JULY 6, 1909.-

Patented Dec. 17, 1912.

'niairnn STATES PATENT rric.

OLOF STAFF AND WILLIAM LARSON, OF LOTHROP, MONTANA.

ROTARY ENGINE.

To all whom it may concern Be it known that we, OLOF STAFF and lVILLiAiiLarson, citizens of the United States, residing at Lothrop, in thecountyof Missoula and State of Montana, have invented certain new anduseful Improvements in Rotary Engines, of which the following is aspecification.

Our invention relates to rotary engines, and more particularly to thatclass of rotary engines wherein a pair of rotors is pro vided, whichhave radially movable blades contacting with the inner face of anexterior cylinder or casing, these blades being retracted as the bladereaches an abutment fixed to the outer casing, this abutment beingprovided on each face with means for the outlet and inlet of steam orother motive fluid, one of the cylinders being connected to the other,so that one cylinder acts as a low pressure cylinder while the otheracts as a high pressure cylinder, the motive fluid being conducted fromthe low pressure cylinder to the high pressure cylinder.

The objects of our invention are to provide a motor of this character,wherein the parts shall be relatively simple, wherein the blades shallbe positively actuated to withdraw them from engagement with theabutment, and further to provide a valve mechanism therefor, whereby therotors may be operated in either direction at will, and the inflow ofthe motive fluid be cut off at any desired point.

The invention consists in the arrangement of parts and details ofconstruction set forth in the accompanying specification andparticularly stated in the claims appended.

For a full understanding of the invention and the merits thereof, and toacquire a knowledge of the details of construction, reference is to behad to the following description and accompanying drawings, in which:

Figure 1 is a perspective view of our improved engine; Fig. 2 is atransverse vertical section of the same; Fig. 3 is a sectional. view onthe line 38 of Fig. 2; Fig. 4t is a view showing the connection of theouter eccentric-ring to the inner, this view being a fragmentarysection; Fig. 5 is a longitudinal horizontal section of the valve casingshown in Fig. 2; Fig. 6 is a section on the line 6-6 of Fig. 2; Fig. 7is a section on the line 77 of Fig. 2; Fig. 8 is a section on the line8-8 of Fig. 2; Fig. 9 is a fragmentary en- Specification of LettersPatent.

Application filed July 6, 1909.

Patented Dec. 1?, 1912.

Serial No. 506,143.

larged section of the edge of one of the rotor caslngs and the rotorshowing the channel therethrough, the section being taken on line 99 ofFig. 10; Fig. 10 is a fragmentary section of the rotor casing showingthe abutment, the inlet and outlet ports therein, the packing stripmovable therethrough, and a portion of the rotor passing the abutment;

Fig. 11 is a perspective view of one of the rotors detached from thecasing and partly broken away, and one of the blades being entirelyremoved; Fig. 12 is a face view of the rotor detached, the shaft and theeccentric hub whereby the blade rings are actuated being shown insection; and, Fig. 13 is a perspective view of the packing plate.

Corresponding and like parts are referred to in the followingdescription and indicated in all the views of the drawings by the samereference characters.

In the drawings, 2 designates a base of any suitable character, adaptedto support the low and high pressure cylinders of the engine.

A designates, generally, the casing of the high pressure cylinder, and Bthe casing of the low pressure cylinder. These casings are cylindricaland are each made in two parts 3 and 4. The lower part 4 has theoutwardly extending base flanges 5 whereby it is attached to the base 2,and is also provided with the outwardly extending flanges 6 at its upperend. The upper portion 3 of each casing is also formed with outwardlyextending flanges 6 which are complementary to the flanges 6, andthereby the upper portion of the casing may be attached to the lower.Both of the casings A and B are made precisely alike. The interior faceof each casing is circumferentially channeled, as at A as shown in Fig.9, thereby providing one-half of the piston space of the engine, .theother half of the piston space being formed by a circumferential channelin the periphery of the rotor. A central shaft 25 passes through both ofthe casings and is supported at its ends in pillow blocks 7 havingthereon any ordinary journal bearings. The rotors are mounted upon thisshaft. These pillow blocks 7 are arranged adjacent to the outer faces ofthe casings. Between the two casings, A and B are lo cated the upwardlyextending pillow blocks 8 and 9 which support the transversely extendingjournal bearing 10 of any desired construction and provided with a capit held in place by bolts, as usual in journal box construction. Theouter and inner ends of each of the casings are closed each by a pair ofpivoted plates, those plates covering the outer ends of the casingsbeing designated 12, while those closing the inner ends of the casingsare designated 15. These are pivoted at their lower ends, as at 12 oneach side of the pillow block 7, so that they may be opened in order topermit the rotors to be examined or repaired. Suitable packing is, ofcourse, placed between the inner faces of the closing plates and theends of the easings A and B. These covering plates are preferably heldin place by stud bolts 13. The covering plates are each cut-away so asto fitclosely over the pillow blocks. The covering plates 15 fit closelyover the journal bearing 10 and its cap, and the cap is cut-away, as at11 to receive the inner edges of the covering plates. The upper ends ofthese plates are provided with cars 16 through which a bolt passes,whereby the plates may be drawn together.

The shaft 25, at its ends, beyond the journal bearing 10, is reduced,and the reduced ends are supported, as before stated, in bearingsmounted upon the pillow' blocks 7. The rotors for the two casings A andB are designated 28. Both of these rotors are preeisely the same (exceptas to size and piston space), and hence the description of one willsuffice for the other.

Referring now to Figs. 9, 11 and 12 it will be seen that each rotorconsists of a disk having on its outer edge the laterally projectingannular flange 30. The periphery of the rotor is formed with acircumferential channel 31 which registers with the channel A formed inthe inside face of the casing. At diametrically opposite points thecircumferential wall of the rotor is radially slitted, as at 82, theface of the flange 30 being recessed, as at 32 on each side of thisslit. Mounted in each slit 32 are the opposed packing strips 33 whichare attached to a carrying plate 34, as shown in Fig. 13, this platefitting in the recess 32 previously referred to, and being held in placeby screws or other suitable means. The packing strips 33 are spaced fromeach other sufficiently to permit a piston blade to reciprocate throughthe periphery of the rotor, and yet not permit a passage of steam fromthe exterior of the rotor into the interior thereof. In other words,these packing strips act as stuffing boxes for the piston blades. Theinner face of the rotor disk is radially grooved, as at 37, to receivethe edges of the piston blades 38 and 39, as seen in Fig. 11. Thesegrooves form guides for the piston blades in their outward and inwardmovement.

Each of the piston blades 38 and 39 is of the same character. They arerounded at their outer ends to fit the rounded channel A formed in theinside face of the rotor casing and the blades are slightly narrowerthan the peripheral flange 30 of the rotor. The inner end of each of theblades is offsetfrom the outer end so as to form a guiding extension 40which is received in a space 4]. between the two guiding blocks 42 whichproject from the inner face of the rotor. It

will be understood that the extension 40 of the blade has free andsliding movement between guiding blocks 42, so that the blade isperfectly free to move radially in the source of its travel.

To the inner ends of each of the blades 38 and 39 is attached aneccentric strap or ring, these being respectively designated by thenumerals 45 and 46. The ring 46 is at t-ached to the blade 38 and thering 45 to the blade 39, and the rings are precisely similar to eachother, except that the ring 46 is less in diameter than the other ring45 and fits therein. The inner ring 46 is provided with a pawl 4bengaging in a recess 45 in the ring 45, and thus both of the rings willrotate as one in either direction and yet be separably removable whendesired, itbeing only necessary to disengage the pawl 46 from thisrecess to disengage the rings from each other. Rigidly attached to butformed in part with the pillow block 7 and projecting from the insideface thereof into the interior of the rotor, is a fixed hollow hub 47which is eccentric to the shaft 25. This hub forms practically aneccentric with which the rings 45 and 46 co-act, the rings 45 and 46being placed within the hollow eccentric formed by the hub 47. In orderto permit the easy removal and adjustmentof the rings 45 and 46, thiseccentric is preferably formed in two parts or sections 47 and 47 thesetwo parts or sect-ions being formed with mating flanges at their endsand connected together by screws or in any other suitable manner, sothat the covering part 47 may be easily removed from 47. The interiorface of the eccentric is annularly recessed, as at 47 to receive anannular flange 45 on the ring 45. The ring 45 is thus locked in placeuntil the removable section 47 is removed. The outer face of the innerring 46 and the inner face of the outer ring are slightly beveled, asshown in Fig. 2, so that the inner ring cannot move outward unless theouter ring is removed. This eccentric extends downward and hence it willbe seen that the blades 38 and-39 will be drawn inward as each movesupward toward the abutment 50, and will be then gradually projectedoutward as it moves downward 011 the other side away from the abutment50.

The shaft 25 passes through the ring 46 and is eccentrically set withrelation to the rings and the eccentric. The inner'ends of the rings 45and 46 are not in the same plane with the inside faces of the pistonblades and hence the blades are connected to the rings by inwardlyprojecting ears 48. It will be plain that upon a rotation of the rotorupon the eccentric 47, the blades will be drawn inward and then forcedoutward, this inward movement of each of the blades occurring at acertain point before it reaches the abutment 50 and the outward movementoccurring after the blades have moved beyond this abutment.

At its uppermost portion, the rotor casing A, on its inside face, isprovided with the abutment 50 which is cast on or otherwise attached tothe inside face of the upper section of the rotor casing. This abutment50 forms the means whereby the steam is admitted to the casing andexhausted therefrom. The abutment at its ends is beveled, as at 51, andan inlet passage 52 extends inward through the shell of the casing A andthrough to one beveled end face of the abutment, while an exhaustpassage 53 also extends through the shell and opens upon the opposedbeveled face of the abutment. This abutment is rounded on its lower faceso as to fit the channel 31. Thus, steam which is admitted through thepassage 52 or inlet port of the rotor, will pass entirely around thechannel of the rotor and will pass out through the exhaust port or passage 53. In order to provide means for preventing any possible leakageof steam through the abutmentor past the same, even at the time when thepiston blade is pass ing the abutment, we provide the packing strip orplate 54 which is carried in a recess 55 in the middle of the abutmentand in the wall of the casing. This packing plate is rounded on itslower edge to fit the channel, and its upper end is reduced, as at 56,and passes upward to the exterior of the casing. A coil spring 57surrounds the reduced end 56 and acts normally to force the packingstrip downward. The resiliency of the spring can be so adjusted as toforce the packing plate inward to a greater or less degree. The recess57 is closed by a plate 57 through which the reduced end 56 of theabutment projects. The edge of the packing plate should fit the channelin the rotor with sufficient tightness to prevent any passage of steamfrom one side of the abutment to the other, even when the piston bladesare passing the abutment, but at the same time it should interfere aslittle as possible with the free rotation of the rotor.

In order to provide for a proper movement of the blades permitting themto pass the abutment 50 and to contact with the walls of the casing assoon as possible after they have passed the abutment, a peculiareccentric relation exists between the rotor casing and the eccentricwhich moves the blades. This relation is shown in Fig. 3. It will beseen from this figure that the inner face of the steam channel formed inthe casings A or B, is not a true circle concentric to the shaft 25, butthat it is ellipsoidal, having a major diameter longer than its minordiameter by the depth of the abutment 50. The lower portion of thisellipse, from the points e e, is concentric with the eccentric 47, andhence, the ends of the blades will contact with the inner face of thesteam channel or cylinder, as it may be called, from one point z to theother point 2 around the lower half of the casing. From the point 2,however, to the abutment 50, the blades will be gradually retracted bythe eccentric 47 and will take a path indicated by the dotted lines 00,this path being concentric to the eccentric L7. The blades willtherefore be fully retracted at the point where they meet the abutment50, and from there to the point a will gradually be projected until atthe point 2 they will come in full contact with the face of the steamchannel. Hence, the steam admission is so regulated that it occurs atthe time that the blade is brought in contact with the face of thechannel at the point or 2, depending upon the direction of motion of therotor. as soon as the blade has reached the point a, steam will enterthrough the inlet passage 52 between the piston blade and the end of theabutment, and the blade will be forced forward in its rotation untilsuch time as it reaches and passes the outlet opening When this occurs,the steam behind the blade will be exhausted, this steam being in turnforced out of the piston space by he next following blade. While we haveshown two blades upon the rotor, we wish it understood that we may useas many blades as desired, two being shown merely for illustrativepurposes.

In order to suitably pack the rotor and prevent the escape of steam atthe junction of the rotor with the incasing cylinder, we bevel each faceof the rotor, at 58, and place within the rotor casing on each sidethereof the packing rings 59, as shown in Figs. 2 and 9. Each packingring, as shown particularly in Fig. 9, has a beveled inner face fittingthe beveled edge 58 of the rotor. The packing is held from any rotationwith the rotor by any suit-able means attaching it to the adjacentcovering plates or the casing.

As before stated, our invention compre hends the provision of a highpressure cylinder from which the exhaust steam shall be carried to a lowpressure cylinder. The steam space formed by the channels A and 81 inthe low pressure cylinder and rotor is of larger area than the likesteam space in the rotor and casing A, so as to provide for theexpansion of the steam in passing from the high pressure to the lowpressure cylinder. The high pressure cylinder A has the two ports orpassages 52 and 53. The low pressure cylinder also has two portscorresponding to the ports 52 and 53. Each of s the ports 52 and 53 areprovided with the upstanding pipe connections 52 and 53, while the twoports of the cylinder B have the upstanding pipe connections 72 and 73,which lead to a valve chest 75. This valve chest consists of acylindrical casing closed at its ends, one of the ends, however, beingprovided with a stuffing box 76 for the passage of the spindle 77 of arotary valve which is designated generically 80. Formed in one piecewith the cylindrical valve chest 75 are the opposed longitudinallyextending chambers 78 and 79, these chambers forming conducting passagesleading from the for ward end of the valve chest to the rear endthereof, or in other words, forming bypasses. The ends of the chamber78is connected to the inlet pipe 52 and 72 of the casings A and B. Each ofthe chambers is divided at its middle by a septum into two parts orchambers 81 and 82. These chambers on each side of the valve chestcommunicate with the interior thereof by the ports 83 and 84. The valvechest itself has an inlet opening at 85 from which a pipe 86 passes toany suitable source of steam or motor fluid supply. This inlet openingis at one end of the valve chest, while an outlet or exhaust opening 87is located at the other end of the valve chest and connects with anexhaust pipe 88 which leads therefrom to any suitable location. Thevalve 80 is cylin drical in cross section. It is provided with a head 90at each end which fits the bore of the valve chest. The middle of thevalve is provided with an outstanding flange or wall 91 which contactswith the valve chest at the middle thereof and intermediate bet-ween theinlet and exhaust ports of the valve chest which lead to the chambers81, S3, 82 and 84. The valve is thus divided into two parts a and b, thepart a acting as the valve for cut ting off and admitting steam to thecasing A, while the'part Z) admits and cuts off the steam to the casingB. The valve is cut away on. each side in the form of a segment of acylinder so that the valve practically forms a two-way valve,permitting, when the valve is in one position, the inlet of steam at theinlet opening 85 to the chest, and the inlet of steam through the portinto the chamber 81, from whence it will pass by the pipe 52 to theinlet port of the casing. The exhaust steam from the casing A will passup the outlet pipe 53 into the opposite side chamber 7 9 of the valvechest. From this chamber, it will pass through the port into the valvechest, and from thence will pass through a diagonal passage 89 cutthrough the middle wall 91 of the valve and into the compartment 5therein. From thence, it will pass by the port into the chamber 83,thence by the pipe 72 to the inlet port of the cylinder casing B, thencearound the rotor, out through the outlet port of the cylinder casing, upthrough the pipe 72, into the chamber 84, from said chamber into therear end of the valve chest and out through the exhaust port 80 to theexhaust 87.

It will be seen that if the valve 80 were not oscillated within thechamber, the steam would be delivered against the blades during nearlythe whole of every revolution and until the blade has passed theabutment. There would he therefore no means of cutting off the steam,and the steam would not act expansively. It is therefore necessary toprovide some means of oscillating the valve 80 so that it will open theport leading to the inlet of the rotor casings, and after a proper timeout off these inlet openings or cut off the main inlet to the valvechest, though preferably the former is the case, as this permits thevalve chest to be used as a reservoir for steam. For the purpose ofoscillating the valve 80, we provide the end of the stem 77 with thetransverse arm 100. One end of this arm is pivotally connected to a link101 which is bent outward and then extends downward over the end of theshaft 25, the link being slotted or bifurcated, as at 102, for thispurpose so as to fit over the shaft. The other extremity of the arm 100is also provided with a pivoted link 103 which extends almost directlydownward and is likewise slotted at its end, as at 104:, to fit aroundthe shaft. these links are spaced sufficiently far apart to accommodatebetween them a double cam 105. This cam, onone lateral half of itsperiphery, is formed with the cam projections 106 and on the other halfwith the alternately placed cam projections 107. Eachof the links isprovided with the inwardly projecting pintles 10S upon which are pivotedthe rollers 109 adapted to contact with the cam projections onthatparticular side of the cam when the links are so moved as to bring oneor the other of the rollers against the face of the cam. This cam isfast upon the shaft 25 and as it rotates, the link whose roller is incontact with its face, will be reciprocated. In order to draw therollers on the links into contact with the faces of the cam, we prolongone of the links, as at 110. This passes through the bi furcated end ofa lever 111 which is pivoted upon a support 112 so as to be held in anydesired adjustment thereon. The extension 110 of the link 101 issurrounded on either side of the lever 111 by coil springs 113, 11 1-.These elastically hold the link in engage ment wit-h the lever 111.Thus, the link will move up or down with the lever, as the lever isactuated, but the springs 114 will The lower ends of hold the roller ofthe link 101 in contactwith its cam face, while the spring 113 will holdthe roller of the link 103 in contactwith this face of the cam so thatwhen the cam projections have passed, the rollers will drop into thespace between the projections. Thus, when either of the links is drawndownward, the valve spindle will be rotatably reciprocated,thusoscillating the valve.

The purpose of the two sets of links and the two sets of cam faces is ofcourse in order to provide for a reversal of the engine, whereby thesteam may be reversely directed to the course of travel previouslystated. In this case, the former outlet ports become the inlet ports,and vice versa. This is secured by operating the lever 111 so as toforce one of the links out of engaging position with the cam, and forcethe other link into such engaging position. This rocks the arm 100 andturns the valve within the valve chest so that it connects, in oneposition, the inlet port with the port which was before the outlet portof. the valve or of that particular chamber, and what was before theinlet port, now becomes the outlet port therefor, this reversal of thevalve of course acting, as ust stated, to direct the motive fluidthrough the engine in a reverse direction to that previously described,as far as regards the individual rotor. Of course the motive fluidpasses first to the high pressure cylinder and then to the low pressurecylinder, and. no reversal in this instance takes place.

It may sometimes happen that the rotor will stop upon the cut-off, andif this is the case, it would be practically impossible to start theengine without turning the rotor past the abutment. Under thesecircumstances, provision must be made for directing the motive fluidinto the other side of the rotor casing so as to force the blades pastthe abutment. It is for this purpose that we provide a cylindrical valvechest 120 which has the port 121 communicating with the inlet end of thevalve chest and with the opposed outlet ports 122 which lead by passages123 to conductor passages 78 and 79 respectively. Mounted within thechamber 120, is the rotatable t-woway valve 124 which, in one positionconnects the inlet passage 121 with the end of the outlet 123, and inthe other position connects it with the other of the outlet ports.

The operation of our invention will be obvious from what has gonebefore. Steam entering the valve chest is directed into the highpressure rotor casing upon the inlet side thereof, and after a blade haspassed the inlet port. The steam forced into this space between theperiphery of the rotor and the inner face of the rotor casing, will actagainst the piston blade to rotate the rotor. After it has rotated asufficient distance, the valve gear will cut off the flow of steam tothe rotor, and the steam will thenceforth act port. Upon reaching theoutlet port, the steam will be forced outward and into the forwardportion of the valve chest, and will be carried through the valve andinto the lateral passage. From thence, it will pass into the inlet sideof the rotor casing 13. In this casing, it will act expansively andunder low pressure upon the blades, in precisely the same manner that itacted in the former case, and will travel around until it reaches anexhaust port, from which it will be forced off and carried out throughthe exhaust pipe. The period of cut-0E may of course be varied byvarying the stroke of the arm 100 or of the cam motion which operatessaid arm. We do not wish to be limited to any particular manner ofoscillating the valve or of changing the amount of cut-off of saidvalve. When it is desired to reverse the engine, it is only necessary tomove the lever 111 so as to throw the other link into engagement withthe cam, and thus turn the valve 80 from one position to a diametricallyopposite position, as before described.

Having thus described the invention, what is claimed as new is 1. In arotary engine, a rotor casing, a rotor shaft, a rotor on the shaftdisposed within the casing, radially movable blades on the rotor, anannular eccentric on the inner face of the rotor casing made insections, and a plurality of rings fitting one within the other anddisposed within said annular eccentric, means for engaging said ringswith each other for movement tomovable blade to one of said rings.

2. In a rotary engine, an outer casing, an abutment on the interior faceof the casing, a rotor shaftextending through the casing, a rotor on theshaft, a radially shiftable blade mounted on the rotor and projectingtoward the inner face of the rotor casing, guides on the rotor in whichsaid blade moves, a fixed annular eccentric surrounding the shaft andextending toward the rotor, and a ring disposed within the eccentric andconnected to said blade.

3. In a rotary engine, an outer casing having a channel formed in itsinner face, an abutment projecting into said channel, a rotor shaftpassing through the casing, a rotor open on one end and mounted on theshaft and having a slot in its periphery, said rotor having a channelextending around its circumference complementary to the channel in thecasing, a radially shiftable blade mounted within the rotor andextending out through the slotted periphery thereof, a fixed annularsectional eccentric surrounding the shaft and projecting into the hollowinterior of the rotor, a ring dis gether, and connections from eachradially expansively until it has reached the outlet posed within theeccentric to which said blade is connected, guides on the interior ofthe rotor for guiding said blade in its radial movement, and means foradmitting steam to the channel on one side of the abutment andexhausting the steam from the channel on the other side thereof.

l. A. rotary engine including a high pressure casing and a low pressurecasing, a shaft passing through both of said casings, rotors mounted onsaid shaft and located one in each of the casings, said rotors beingchanneled upon their periphery, radially movable blades carried by eachrotor and extending into the channel, a fixed eccentric located adjacentto each rotor, connections between the eccentrics and blades whereby thelatter may be readily moved upon the rotation of the rotor, an abutmentlocated in each casing and. extending down into the channel of therotor, each of said abutments having an inlet port located on one endthereo-f'and an outlet port on the other, a valve casing extendingtransversely over the two casings, a rotatable cylindrical valve mountedin the valve casing, said valve being solid at its middle and cut awayon each side of the middle solid portion, a steam inlet pipe leadinginto the upper portion of the valve casing, opposed longitudinallyextending conducting pipes mounted parallel to the main valve casing andhaving openings in their sides leading into the main valve casing on.each side of the centrally solid portion of the valve, a septum crossingsaid conducting pipes in the middle thereof and dividing the pipes intwo portions, and pipes leading from each end of the conducting pipes tothe ports on each end of the abutments in the high and low pressurecasings.

5. In a rotary engine, a rotor comprising a disk-like body having alaterally projecting peripheral annular flange extending at right anglesto the face of the rotor, said flange being slotted transversely, ashaft on which the rotor is mounted, radially movable blades carriedwithin the rotor and extending out through said slots in the flange, acasing surrounding the rotor, a fixed eccentric surrounding the shaftbut non-rotatable therewith and projecting through the open side of therotor, means for operatively engaging the fixed eccentric with theblades to shift the latter radially as the rotor rotates, and removableplates closing the side of the casing and embracing the base of thefixed eccentric.

6. In arotary engine, a rotor comprising a disk-like body having alaterally projecting peripheral flange, said rotor being open on oneside, said flange being slotted at a plurality of points, the outer faceof the flange forming the periphery of the rotor being channeled, ashaft on which the rotor is mounted, radially movable blades carriedwithin the rotor and extending out through the slots in the flange, acasing surrounding the rotor and formed with an abutment extending downinto the channeled face of the rotor, said abutment being provided withports opening on one side thereof, a fixed annular eccentric surroundingthe shaft of the rotor but non-rotatable therewith and projecting intothe hollow interior of the rotor, rotatable members operatively engagingwith the eccentric and shifted radially by said eccentric, said membersbeing operatively attached to the blades, and removable plates closingthe side of the casing with which the edge of the peripheral flange ofthe rotor contacts, said plates when closed embracing the fixedeccentric.

7. In a rotary engine, a rotor comprising a disk-like body having alaterally project ing peripheral flange, said rotor being open on oneside, said flange being slotted at a plurality of points, a shaft onwhich the rotor is mounted, radially movable blades carried within therotor and extending out through the slots in said flange, a casingsurrounding the rotor and provided with an abutment formed with inletports on each side thereof, a fixed annular eccentric surrounding theshaft and projecting into the hollow interior of the rotor, a pluralityof rings disposed one within another and located within the annulareccentric andshiftable thereby, said rings each being connected with acorresponding blade on the rotor.

In testimony whereof we our signatures in presence of two witnesses.

OLOF STAFF. [1,. s. WILLIAM LARSON. [n s.l Witnesses:

H. H. Mona,

R. J. BROWN.

Copies of this patent may be obtained for five cents each, by addressingthe Commissioner of Patents, Washington, D. G.

